Did they know they would lose?

[AdamGB]

The will have both known that it could affect them and take them out of their depth. Maybe not by how much but they would have known it was taking them outside of their comfort zone.

Like has been said - they also knew how much they would get paid.

[fan johnny]

IMO with De La Hoya's case it's a no brainier, get the money and get out!

In Marquez's case it's a little more difficult because he could have lined up a number of fights (how many would breach $1M) and he'd still be looking for that trilogy with Pacquiao. Can he revive his career once again and still line up a third fight? Only time will tell if he actually made the right move when it comes to career earnings.

[CFH]

In Marquez' case, he's a proud fighter with a storied resume and I'm sure he thought he could be PBF. The pile of money he was earning probably helped convince him taking the fight was the right thing to do, but I'm sure he thought he could win. I understand the argument that he never made the money he should have and as such allowed that to influence his decision making, and there could be some validity to it, but I sure he thought he could win right up until the middle of the fight.

For Oscar, I think pretty much the same thing. He sure as shit didn't need the money, though he strikes me as the type of person who just loves the limelight and I think that was his primary motivation for fighting Pac. He wanted to be involved in one last megafight and I genuinely think he thought Pac would just be too small for him, regardless of the effects cutting the weight had. I'm sure right around round 1 or 2 he realized he was fucked though.

Just my .02